package com.waldura.tw;

import java.util.List;

/**
 * This interface defines the object storing the graph of all routes in the
 * system.
 * 
 * @author Renaud Waldura &lt;renaud+tw@waldura.com&gt;
 * @version $Id: RoutesMap.java 2367 2007-08-20 21:47:25Z renaud $
 */
public interface RoutesMap {

    /**
     * Enter a new segment in the graph.
     */
    public void addDirectRoute(City start, City end, int distance);

    /**
     * Get the value of a segment.
     */
    public int getDistance(City start, City end);

    /**
     * Get the list of cities that can be reached from the given city.
     */
    public List<City> getDestinations(City city);

    /**
     * Get the list of cities that lead to the given city.
     */
    public List<City> getPredecessors(City city);

    /**
     * @return the transposed graph of this graph, as a new RoutesMap instance.
     */
    public RoutesMap getInverse();
}
